Abstract: Imperata cylindrica is an invasive plant species that threatens diversity and forest productivity in southeastern ecosystems. We examined the effects of disturbance events, particularly fire and hurricane/salvage harvesting, to determine the effects onI. cylindrica abundance in longleaf pine (Pinus palustris) forests in the Florida panhandle. Areas that were burned or had greater biomass removal following a hurricane had a greater number of I. cylindrica patches and larger patch size. These results highlight the importance of disturbance events on expanding invasive species populations in this region and are likely applicable for other invasive species as well. Monitoring and treatment should follow disturbance events to ensure that invasive species populations do not exceed unmanageable levels.

Abstract: A field-based study was performed to broaden our knowledge of operational efficiency losses associated with the neglect of the proper maintenance of the delimbing and feeding mechanisms of a harvester. The post-harvest assessments of industrial round-wood (IRW) processing damage, fuel consumption and productivity were examined in clearcutting operations. Observations were made of seven combinations of wear levels of feed rollers (A—heavy, B—medium, C and C’—without wear) and sharpening states of delimbing knives (1—incorrect, 2—correct), depending on the degree of feed roller wear and matching of angles of knife blades to the technical requirements. The processing defects of IRW were broken down into unprocessed branches, bark stripping, and damage caused by feed roller spikes. The results were then compared with the effective quality requirements, and the IRW losses in terms of the reject rates (RR) were determined in the context of the technical condition. The most frequent damage was by unprocessed branches. The harvester with correctly sharpened knives produced the minimum RR (4% of pine, 6% of spruce and 6% birch logs). The quality of IRW harvested under B1 and C1 resulted in 6%, 6% and 8%. A1 turned out to be the lowest (12%, 10% and 8%). Improvement in the maintenance of delimbing knives can reduce the RR of IRW by 5%. Timely restoration of worn-out rollers can increase productivity by 2% and reduce fuel consumption by 5%.

Abstract: Native or exotic woody plants can proliferate in dry and moist eucalypt ecosystems shading out many other native species, contributing to chronic decline of eucalypts and reinforcing unnatural fire regimes and nutrient cycling processes. Whether native or exotic, they proliferate as a consequence of disturbances which impact directly on these ecosystems. The most extensive ongoing disturbance since European occupation of Australia has been the disruption of frequent mild burning by humans. This burning maintained dynamically stable nutrient cycling processes and a competitive balance in dry and moist eucalypt systems and prevented plant “invasions”.

Abstract: Plants alter soil characteristics causing changes in their subsequent growth resulting in positive or negative feedback on both their own fitness and that of other plants. In a greenhouse study, we investigated whether the sign and strength of feedback changed across two distinct soil types, and whether effects were due to shifts in biotic or abiotic soil traits. Using soils from two different locations, we examined growth of the exotic invasive shrub, Lonicera maackii and the related native shrub, Diervilla lonicera, in unconditioned soils and in soils conditioned by previous growth of L. maackii, D. lonicera, and Fraxinus pennsylvanica. In a sandy acidic soil, L. maackii showed positive feedback in unsterilized soils, but its growthdecreased and positive feedback became negative with sterilization in this soil. In a loamy circumneutral soil, L. maackii displayed neutral to negative feedback in unsterilized soils, but sterilization significantly increased growth in all conditioning treatments and caused feedback to become strongly negative.Native D. lonicera displayed negative feedback in unsterilized soil of both the sandy and loamy types, but sterilization either eliminated or reversed feedback relationships. Soil conditioning by L. maackii and F. pennsylvanica had very similar feedbacks on L. maackii and D. lonicera. While some abiotic soil traits varied across soil types and were affected by conditioning, soil biota sensitive to sterilization were apparently important mediators of both positive and negative feedback effects.

Abstract: Recreation activity preferences in forest settings were explored in a scene preference study. The importance of type of human intervention and the level of biodiversity for preference and intention to engage in recreation activities were examined in a sample of forestry and social science students in Sweden. Results showed that forestry students displayed an almost equally strong preference for natural-looking scenes as for scenes with traces of recreation (e.g., paths), whereas social science students preferred recreational scenes the most. Least preferred were scenes with traces of forest management. Different forest settings were furthermore preferred for different recreation activities. Recreational settings were favored for walking and going on outings, and natural-looking settings were more appreciated for picking berries or mushrooms. Respondents displayed a stronger intention to study plants and animals in high biodiversity settings and the intention to exercise was stronger in low biodiversity settings. Implications for future land use planning and forest management are discussed.

Abstract: Temperate conifer forests in the Colorado Front Range are fire-adapted ecosystems where wildland fires leave a legacy in the form of char and charcoal. Long-term soil charcoal C (CC) pools result from the combined effects of wildland fires, aboveground biomass characteristics and soil transfer mechanisms. We measured CC pools in surface soils (0–10 cm) at mid-slope positions on east facing aspects in five continuous foothills shrubland and conifer forest types. We found a significant statistical effect of vegetation type on CC pools along this ecological gradient, but not a linear pattern increasing with elevation gain. There is a weak bimodal pattern of CC gain with elevation between foothills shrublands (1.2 mg CC ha−1) and the lower montane, ponderosa pine (1.5 mg CC ha−1) and Douglas-fir (1.5 mg CC ha−1) forest types prior to a mid-elevation decline in upper montane lodgepole pine forests (1.2 mg CC ha−1) before increasing again in the spruce/subalpine fir forests (1.5 mg CC ha−1). We propose that CC forms and accumulates via unique ecological conditions such as fire regime. The range of soil CC amounts and ratios of CC to total SOC are comparable to but lower than other regional estimates.

Abstract: To assess effects of low-intensity fire, we combined two silvicultural prescriptions with prescribed fire in the California Cascade Range. In the first treatment, two 100-ha stands were thinned to reduce density while retaining old-growth structural characteristics, yielding residual stands with high structural diversity (HSD). Two other 100-ha plots were thinned to minimize old growth structure, producing even-aged stands of low structural diversity (LSD), and one 50-ha split-plot from each treatment was burned. In addition, two 50 ha old-growth Research Natural Areas (RNA) were selected as untreated reference plots, one of which was also burned. Fire treatments profoundly altered mite assemblages in the short term, and forest structure modification likely exacerbated that response. Sampling conducted two years following treatment confirmed a continuing decline in oribatid mite abundance. Oribatid species richness and assemblage heterogeneity also declined, and community dominance patterns were disrupted. Oribatid responses to fire were either more intense or began earlier in the LSD treatments, suggesting that removal of old-growth structure exacerbated mite responses to fire. Prostigmatids recovered quickly, but their populations nonetheless diminished significantly in burned split-plots. Mite assemblage responses to prescribed fire were continuing nearly two years later, with no clear evidence of recovery.

Abstract: Over 400 species of insects have been found in association with eastern hemlock in the southern Appalachians. Eastern hemlock stands provide an ideal habitat for all life stages of mycetophilids. However, the diversity, distribution and co-occurrence patterns of these species throughout the tree canopy are unknown. This study was initiated to evaluate abundance, species richness and species composition within three designated strata in the canopy of eastern hemlock, assess species for vertical stratification patterns, and determine if co-occurrence patterns of mycetophilid species are random or non-random. During this study, 24 species representing 14 genera were identified and evaluated. Mycetophilid abundance, species richness and composition differed among the lower, middle, and upper strata. Unique assemblages were identified in each stratum, indicating vertical stratification. The upper stratum of the canopy had four exclusive species, the middle had six exclusive species, and the lower stratum had nine exclusive species. The co-occurrence pattern of mycetophilid species in the canopy of eastern hemlock was non-random.

Abstract: The impact of invasive plant species in national parks and forests in Vietnam is undocumented and management plans have yet to be developed. Ten national parks, ranging from uncut to degraded forests located throughout Vietnam, were surveyed for invasive plant species. Transects were set up along roads, trails where local people access park areas, and also tracks through natural forest. Of 134 exotic weeds, 25 were classified as invasive species and the number of invasive species ranged from 8 to 15 per park. An assessment of the risk of invasive species was made for three national parks based on an invasive species assessment protocol. Examples of highly invasive species were Chromolaena odorataand Mimosa diplotricha in Cat Ba National Park (island evergreen secondary forest over limestone); Mimosa pigra, Panicum repens and Eichhornia crassipes in Tram Chim National Park (lowland wetland forest dominated by melaleuca); and C. odorata, Mikania micrantha and M. diplotricha in Son Tra Nature Conservation area (peninsula evergreen secondary forest). Strategies to monitor and manage invasive weeds in forests and national parks in Vietnam are outlined.

Abstract: The ability to restore American chestnut (Castanea dentata)through the planting of blight-resistant (Cryphonectria parasitica) trees is currently being tested. Forest-based research on the species’ silvicultural requirements and chestnut blight development are lacking. Pure American chestnut seedlings were planted in a two-age shelterwood forest with low residual basal area and in a midstory-removal treatment with high residual basal area. Survival did not differ between silvicultural treatments and averaged 67 percent across both treatments by the fifth year. Trees in the two-age shelterwood were 2.36 m and 16.8 mm larger in height and ground-line diameter, respectively, compared to trees in the midstory-removal by the fifth growing season. Blight occurrence was not affected by silvicultural treatment. Exploratory analyses indicated that seedling grading at planting and keeping trees free-to-grow through competition control would have resulted in a two-year gain in height and GLD growth in the two-age shelterwood treatment. The two-age shelterwood represented the most efficacious prescription for chestnut restoration, but the midstory-removal prescription may offer a reasonable alternative in areas where harvesting must be delayed.

Abstract: Phosphorus is widely deficient throughout the southern pine region of the United States. Growth responses to P fertilization are generally long-lasting in a wide range of soil types, but little is known about fertilization rates and long-term P cycling and availability. In 1982, exceptionally high P fertilization rates (0, 81, 162, and 324 kg P ha−1) were applied to a loamy Ultisol in central Louisiana, USA. We measured vegetation responses at age 27 years and sequentially extracted soil P to 1 m to elucidate potential P availability into the next rotation. Loblolly pine responded well to the lowest fertilization rate; total biomass was 39% greater in the fertilized plots compared to the unfertilized plots, but higher fertilization rates had no effect, presumably due to induced N-limitations. What little fertilizer P was found in the soils was in the moderately labile NaOH fraction in the surface 20 cm, and may be slowly available to the next pine rotation. Normal rates of P fertilizer will maintain elevated available P well into a second rotation in loamy Pleisteocene Ultisols of the western Gulf Coastal Plain. Exceptionally high rates were not effective at increasing potentially available P beyond normal rates.

Abstract: Changes in climate are predicted to significantly affect the productivity of trees in the Great Lakes region over the next century. Forest management decisions, such as initial stand density, can promote climatic resiliency and moderate decreased productivity through the reduction of tree competition. The influences of climate (temperature and precipitation) and forest management (initial stand density) on the productivity of red pine (Pinus resinosa) across multiple sites within Huron National Forest, Michigan, were examined using dendrochronological methods. Two common planting regimes were compared in this analysis; low initial density (<988 trees per hectare) and high initial density (>1977 trees per hectare). Low initial density stands were found to have a higher climatic resilience by combining equal or greater measures of productivity, while having a reduced sensitivity to monthly and seasonal climate, particularly to summer drought.

Abstract: Longleaf pine (Pinus palustris Mill.) is an important tree species of the southeast U.S. Currently there is no comprehensive stand-level growth and yield model for the species. The model system described here estimates site index (SI) if dominant height (Hdom) and stand age are known (inversely, the model can project Hdom at any given age if SI is known). The survival (N) equation was dependent on stand age and Hdom, predicting greater mortality on stands with larger Hdom. The function that predicts stand basal area (BA) for unthinned stands was dependent on N and Hdom. For thinned stands BA was predicted with a competition index that was dependent on stand age. The function that best predicted stand stem volume (outside or inside bark) was dependent on BA and Hdom. All functions performed well for a wide range of stand ages and productivity, with coefficients of determination ranging between 0.946 (BA) and 0.998 (N). We also developed equations to estimate merchantable volume yield consisting of different combinations of threshold diameter at breast height and top diameter for longleaf pine stands. The equations presented in this study performed similarly or slightly better than other reported models to estimate future N, Hdom and BA. The system presented here provides important new tools for supporting future longleaf pine management and research.

Abstract: We perform simulations using the integrated Land Use in Rural New Zealand (LURNZ) model to analyze the effect of various New Zealand emissions trading scheme (ETS) scenarios on land use, emissions and output in a temporally and spatially explicit manner. We compare the impact of afforestation to the impact of other land-use change on net greenhouse gas emissions and evaluate the importance of the forestry component of the ETS relative to the agricultural component. We find that the effect of including agriculture in the ETS is small relative to the effect of including forestry. We also examine the effect of land-use change on the time profile of net emissions from the forestry sector. Finally, we present projections of future agricultural output under various policy scenarios.

Abstract: Successful management of national forests in the United States requires Forest Service personnel to collaborate with the public, including individuals living in communities near national forest lands. Collaboration enables agency personnel to build long-term trusting and reciprocal relationships with local communities through their ongoing planning processes. However, frequently agency personnel do not have the tools or data necessary to measure the strength of relationships that exist between the agency and local communities. A rapid social capital assessment protocol is presented that can be used by agency personnel and social scientists as a tool for gauging the existence and strength of Forest Service—community relationships. The utility of the protocol is illustrated by describing findings from two pilot tests conducted in communities near the Tombigbee National Forest in Mississippi and the Nantahala National Forest in North Carolina. Barriers to effective Forest Service—community relationships are highlighted and opportunities for social capital development, such as utilizing local news outlets, are presented.

Abstract: A recent policy response to halting global forest deforestation and degradation, and any resulting greenhouse gas emissions is REDD+, which also includes the role of conservation, sustainable management of forests and enhancement of forest carbon stocks. Although still in its infancy, the success of REDD+ will depend significantly on whether it can be economically viable and if any resulting payments are sufficient to cover the opportunity cost plus any transaction cost. Where tenure security over forest is weak, REDD+ can pose a risk for forest communities, who could be dispossessed, excluded and marginalized. This review of existing studies explores how payment for avoided deforestation, and forest tenure impact the success of REDD+ projects in terms of effectiveness, efficiency and equity. Effectiveness refers to the difference between deforestation with and without REDD+, efficiency refers to avoiding deforestation at minimal cost, and equity refers to the implication of REDD+ on benefit sharing. We conclude that the potential success or failure of REDD+ as a means to reduce deforestation and carbon emission on forest commons depends critically on designing projects that work within existing informal tenure institutions to ensure that carbon storage benefits align with livelihood benefits.

Abstract: Fire-adapted forests of the Lake States region are poorly studied relative to those of the western and southeastern United States and our knowledge base of regional short- and long-term fire effects on soils is limited. We compiled and assessed the body of literature addressing fire effects on soils in Lake States forests to facilitate the re-measurement of previous studies for the development of new long-term datasets, and to identify existing gaps in the regional knowledge of fire effects on forest soils. Most studies reviewed addressed fire effects on chemical properties in pine-dominated forests, and long-term (>10 years) studies were limited. The major gaps in knowledge we identified include: (1) information on fire temperature and behavior information that would enhance interpretation of fire effects; (2) underrepresentation of the variety of forest types in the Lake States region; (3) information on nutrient fluxes and ecosystem processes; and (4) fire effects on soil organisms. Resolving these knowledge gaps via future research will provide for a more comprehensive understanding of fire effects in Lake States forest soils. Advancing the understanding of fire effects on soil processes and patterns in Lake States forests is critical for designing regionally appropriate long-term forest planning and management activities.